The present disclosure relates to a display system using a liquid crystal display panel and an image data processing circuit used for the display system.
From among technologies applied for driving a liquid crystal display panel for image display, known is an overdrive technology of improving poor response in color change of pixels.
Namely, a liquid crystal display panel, for example, included in a television receiver refreshes a display image in a frame cycle such as 1/60 sec. One sixtieth seconds corresponds to approximately 16 msec. Herein, when a display color of a pixel in the liquid crystal display panel changes from a specific display color to another display color, there is sometimes a case where the color change takes place with a delay later than 16 msec due to relationship between the tones of the two display colors. Such a delay in color change causes an afterimage in the liquid crystal display panel which is not in an image to be displayed by nature, this deteriorating quality of the display image.
Here, the overdrive technology is a technology of changing color change (tone change) to be delayed later than the frame cycle to tone change for compensating the delay, preventing such an afterimage from arising. The tone change to be delayed later than the frame cycle is determined from tone change status of each pixel by referring to a beforehand prepared table. In case of determination of the tone change to be delayed later than the frame cycle, an overdrive circuit performs correction of the relevant pixel from the color by nature to a color with a tone stored in the table. Or the overdrive circuit prepares a calculation formula for calculating a correction value and obtains a tone corrected from the calculation formula using two tones of a tone in the current frame tone and a tone in the previous frame. The overdrive circuit obtains color data for the corrected tone, this attaining display in which an afterimage is suppressed.
Japanese Patent Laid-Open No. 2005-107491 discloses a liquid crystal display apparatus capable of improving a response rate of the display image by the overdrive.